/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.naming.resources;

import javax.naming.NamingEnumeration;
import javax.naming.NamingException;
import java.util.Enumeration;
import java.util.Vector;

/**
 * Naming enumeration implementation.
 *
 * @author Remy Maucherat
 */
public class RecyclableNamingEnumeration<E>
		implements NamingEnumeration<E> {


	// ----------------------------------------------------------- Constructors

	/**
	 * Entries.
	 */
	protected Vector<E> entries;


	// -------------------------------------------------------------- Variables
	/**
	 * Underlying enumeration.
	 */
	protected Enumeration<E> enumeration;

	public RecyclableNamingEnumeration(Vector<E> entries) {
		this.entries = entries;
		recycle();
	}


	// --------------------------------------------------------- Public Methods

	/**
	 * Retrieves the next element in the enumeration.
	 */
	@Override
	public E next()
			throws NamingException {
		return nextElement();
	}

	/**
	 * Determines whether there are any more elements in the enumeration.
	 */
	@Override
	public boolean hasMore()
			throws NamingException {
		return enumeration.hasMoreElements();
	}

	/**
	 * Closes this enumeration.
	 */
	@Override
	public void close() throws NamingException {
		// NO-OP
	}

	@Override
	public boolean hasMoreElements() {
		return enumeration.hasMoreElements();
	}

	@Override
	public E nextElement() {
		return enumeration.nextElement();
	}


	// -------------------------------------------------------- Package Methods

	/**
	 * Recycle.
	 */
	void recycle() {
		enumeration = entries.elements();
	}


}

